I have just completed my early v8 valley pan leak repair. (Inlet manifold off) I will comment on that on a previous started post, but I'm now stuck, with the car starting and immediately cutting out.
It will fire up ok, and rev up, for 1second, and immediately cut out. I have fuel pressure, though possibly have air trapped in rail, even after venting/squirting from shraeder valve....I have double checked I located all the injectors, and have even re located them both sides. I have no spare connectors (electrical) and definitely have the knock sensors bolted back on. I'm sure I have an electrical issue. As it's going into 'engine system failure' ( I think that's what it says) on the pixel display. I have no diagnostic, as the laptop that runs my alcomms, has had a hissy fit, and can't recognise it. I've emailed for another download, but have no reply as of yet. I just wonder what a broken knock sensor would do to an engine...or air in the fuel rail...
I can confirm I did not unplug the camshaft sensors, and I did disconnect the battery whilst working. Etc.
Can't think I have broken the MAF as it was put aside very early on.

As said, car fires, and immediately cuts out. Every time.

Gonna have a cup of tea, and swear at a bit....

Last edited by johnboyairey on 4th May 2016 10:17am. Edited 1 time in total

I assume you have checked for air leaks as well ?? Too much air because a hose is off, could let the ECU think something major is wrong maybe ?

My old 4.2 SC got a complete fuel system / inlet clean job and it was fine afterwards (new fuel pump/filter as well). We didn't have to do anything odd to it to get it going. MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Update, -got the alcomms software going...cleared all faults, still same. Disconnected battery, left to die, and reconnected. Checked faults....still same. Starts.. Fires up, and immediately dies, as it reaches about 1220 rpm, and if left, MIL light appears. Seems electrical.
...but...I took off the MAF and it runs and chugs.for, a few more seconds....checked connections....and after relacement.. Runs one second and dies!
Checked all air connections, no intake leaks.

I remember that the MAF is not that expensive, maybe fork out for a new one to eliminate the MAF being the issue. It is not very likely that the MAF just failed while you were doing this work but the fact that it makes a difference in or out makes me suspicious............ Maybe give the current one a good clean as well.

I bought a new one because my 4.2 SC was not driving well and cleaning the MAF didn't make a difference, nor did the new MAF by the way. But that is how I found out the MAF is not very expensive.

By the way, have you checked the MAP sensor whether that is OK ?? It sits at the back of the manifold if I remember correctly.

Maybe also try to disconnect and reconnect every connector, just to make sure. Also check if they are clean, not that some oil or other crap fell into one during the work and causing issues now. MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

what codes are showing ?

afaii if the maf is u/s it defaults to a usable setting so still should run okish

Update, I reset all historic codes, and now I'm getting no codes. ...one other observation, if I try and Rev up the engine as I start it, it will Rev up and die within one second, it has sufficient intake roar, to tell me that I must have an intake huge leak, so guessing the inlet manifold gaskets, may have moved or dislodged as I was fitting it, so will remove intake manifold today, and recheck everything.

At least it runs, if only for one second. Guessing no sensor apart from O2 sensors can detect the huge air leak.

I took the inlet manifold off, and checked the gaskets.....all seems ok, so I replaced all parts, and tried it, and this time it went first time, and is running fine.

Not explained, but, I guess it was something along the line of "measure twice, cut once" type of repair. -something must have been wrong.
So I shall get my bucket out now and treat it to a nice springtime wash!

 MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

That's a weird one John.... throttle body plug maybe...???

Oh well, who cares, it's going now.....  Pete

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2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
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2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
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